The present invention relates to a diagnostic nuclear magnetic resonance apparatus, and more specifically to a diagnostic nuclear magnetic resonance apparatus capable of being divided into three parts for transportation and of being assembled on-the-spot.
When applying nuclear magnetic resonance (hereinafter abbreviated NMR) to the diagnosis of a human disease, a subject is placed in a uniform magnetostatic field, an inclined magnetic field is superposed on the uniform magnetostatic field, and an exciting rotary magnetic field is then applied to produce an NMR phenomenon. An NMR signal delivered from the subject is detected, and information on the projected area of the subject is obtained. Image information on at least one of the spin densities and relaxation time constants of a specific atomic nucleus of the subject can be obtained by subjecting the projection information to image reconstruction processing. A diagnosis is made on the basis of this image information.
In a diagnostic NMR apparatus, a pair of large air-core coils are arranged in alignment with each other, and a pair of small air-core coils are disposed in alignment with the large coils so that the large coils are sandwiched between the small coils. A uniform magnetostatic field is produced by energizing these four symmetrically arranged air-core coils.
In order to produce an NMR phenomenon, the uniform magnetostatic field needs to be high in intensity and uniform in the image region in which the subject is placed. Accordingly, the four air-core coils are large-sized and heavy in weight. The four air-core coils apply great magnetic forces to one another, so that a heavy load is imposed on the support frames which fix the air-core coils. In order to securely support the air-core coils in an accurate positional relation, therefore, the frames are expected to have high mechanical strength and rigidity. Thus, the frames themselves are increased in size and weight. Consequently, in installing the NMR apparatus in a treatment room of a hospital, transportation, carrying-in, setting-up, and other operations should be very difficult. If the entrance of the treatment room is narrow, it will be impossible to install the NMR apparatus in the room. Moreover, limited room size will put restrictions on the size of the apparatus and hence on its performance.